Cook rice according to package directions. Let stand uncovered, until cooled. Fluff with a fork.

Bring a large pot of lightly salted water to a boil; add yellow wax beans and cook 3 minutes; add sugar snap peas and continue to cook 1 minute, until bright green and very crisp-tender. Drain; refresh under cold water. Drain on a paper towel.

In a large salad bowl, whisk yogurt, balsamic vinegar, olive oil, garlic, salt, and pepper until blended. Remove 1/4 cup dressing to a small cup.